1. Technical Field
This invention relates to the field of speech recognition and more particularly to a method and system for improving overall speech recognition by intentionally degrading utterance pronunciations.
2. Description of the Related Art
Recognition accuracy of a speech recognition system can be lowered by various factors. One possible recognition failure can be do to substitution, where an incorrect word is substituted for the word that was expected. For example, if the user says “Dial” but the system recognizes “Call” then the word “call” was substituted for “dial”. Often times, a certain substitution is prevalent for a particular speech recognition grammar. For example, if the dial to call substitution occurs frequently during operation it would be a known confusable pair. Using statistically significant data sets, accuracy testing can be performed to identify weaknesses in a particular grammar set. From the resulting information, it is possible to identify possible confusable pairs. Past methods to improve these confusable pairs centered on improving the pronunciations for the expected word to try and match a wider spectrum and give the system more choices.